Mower



sept 7, 1943 B. s. OBERLINKA l 2,328,838

MOWER Filed Jan. 15, 1941 A:s sheets-sheet 1 0o, M, .4 OQ .nk www 4 \WSept. 7,1943. B. OBERLINK MOWER Filed Jan. 15, 1941 @xm/M Sept. 7, 1943.B.` s. ERLINK v MowER Filed Jan. 15, 1941' 5 Sheets-Sheet 3 :.llmiflSept. 7, 1943. B. s. oBERLlNK 2,328,838

MowER FiledI J'an. 15, 1941 v 5 Sheets-Sheet 4 Patented Sept. 7, 1943MOWER.

Boyd S. Oberlink, Milwaukee, Wis., assignor to Allis-ChalmersManufacturing Company, Milwaukee, Wis., a corporation of DelawareApplication January' 15, 1941, Serial No. 374,426

14 claims.

` being preferably'such that it may be raisedto a vertical transportposition; in which the knife bar is reciprocated with a full strokethroughout said range of vertical adjustment of the cutter bar; inwhich' the cutter bar may.be adjusted from a position in which it restson the ground to an elevated position parallel with the ground; in whichthe cutter bar may be tilted about an axis extending 'longitudinallythereof for the purpose of adjusting the cutting height when the cutterbar rides on the ground; in which the cutter bar may break back from itscutting position transversely of the tractor if it encounters anobstruction, such as a large stone or a tree stump hidden in the grass;and in which the drive mechanism for the knife bar remains connectedwith the knife bar and continues to operate during said break-backmovement of the cutter bar. i

A further objectvof the invention is to provide an improved mower headwhich is constructed to afford the mentioned vertical adjustment andbreak-back movement of the cutter bar, and the mentioned full stroke ofthe knife bar through- .out the range of said vertical adjustment of thecutter bar, and which mower head also provides for the mentioned abilityof the knife bar drive to remain connected with the knife bar and tocontinue to operate during said break-back movement of the cutter bar.

A further object of the invention is to provide a `mower head of thementioned character in which the driving mechanism for the knife bar issubstantially shielded by the frame structure of the head. v

A still further object of the invention is to provide a compact andsturdy mowerhead which operates efciently and which is capable of severeusage, as in a highway mower, without undue wear. Y

The foregoing and other objects and advantages of the invention and theoperation of a -device constructed in accordance therewith will beapparent from theI following description of a preferred embodiment ofthe invention. Re-

parts in the various views;

ferring to thel accompanying drawings forming part of this specicationand in which like reierence characters designate the same or similarFig. 1 is a perspective view of a tractor mower with the cutter baradjusted to a raised position for cutting on an incline laterally of thetractor;

Fig. 2 is a rear view of the machine shown in Fig. l with the cutter baradjusted to a horizontal position, part of the tractor being broken awayto expose details of the mowing attachment;

Fig. 3 is an enlarged rear view, partly in section, of the mower headand associated parts shown in Figs. 1 and 2, the lower section of the'mower head being shown in section on line IH- t III of Fig. 5. The mowerhead is shown in two positions, one in full lines, which corresponds tothe position in whichthe mower head is shown in Fig. 2; and the other indash-dotted lines, which corresponds approximately to the position inwhich the mower head is shown in Fig. 1;

Fig. 4 is a side view, partly in section, of the mower head andassociated parts shown in Fig. 3, the view being taken from the outerend of the cutter bar towards the tractor; and the inner cutter bar shoebeing shown in section on line IV-IV of Fig. 5; y

Fig. 5 isa top view of the mower head and associated parts shownin Figs.3 and 4, the mower head being shown in full lines in a normal workingposition in which the cutter bar extends transversely of the tractor,and in dash-dotted lines in a partly broken-back position to which itmay move when the cutter bar is driven against an obstruction;

Fig. 6 is a detail view of the cutter bar; and

Fig. 7 is a section on line VII-VII of Fig. 6.

Fig. 1 of the drawings shows a tractor mower comprising a wheel typetractor and a mowing attachment mounted thereon for cutting grass orsimilar vegetation at the'right side of the tractor. The tractorcomprises a body generally indicated by the reference character l whichis supported at opposite sides on front and rear wheels,the front andrear wheels at the right side of the tractor being indicated by thereference characters 2 and 3, respectively. The front and rear wheels atthe left side of the tractor are axially -alined with the iront and rearWheels at the right side of the tractor, the left front wheel beingshown in Fig. 1 and indicated by the reftending longitudinally of thetractor.

tracking relation to the front wheels 2 and 4, as usual.

y The body of the tractor comprises a rear axle structure 1 indicated inFig. -2 on which the -rear wheels 3 and 6 are mounted, and aconventional power unit and transmission mechanism are arranged in frontof the rear axle structure as may be seen from Fig. 1. The body of thetractor. also includes ay U-shaped frame 8 which is secured at its rearend to the rear axle structure 1 and which is supported on the axle ofthe front wheels by means of a U-shaped support 9 which is pivoted tothe front axle at II.

Mounted on the U-shaped frame 8 at the right side of the tractor is abracket I2 which has an upwardly and outwardly' extending arm I3 and adownwardly and inwardly extending portion I4 as best shown in Fig. 2.

Pivotally mounted at the lower end of the downwardly extending portionI4 of the bracket v I2 is a drag frame comprising a pair of arms I6 andI1 which are rigidly connected with each other by a web I8 shown in Fig.2. `The arms I6 and I1 are supported at their inner ends on suitablebearings of the bracket portion I4 for swinging movement about ahorizontal axis ex- The arms I6 and I1 terminate at their outer ends,remote from their pivotal connections with the lower bracket portion I4,in semicircular bearing portions, and bearing caps I9 and 2| are securedto the semicircular bearing portions to form a pair of cylindricaljournal bearings at the outer ends of the drag frame arms I6 and I1.

Pivotally mounted in the journal bearings at the outer ends of the dragframe arms I6 and I1 is a mower head which is constructed in twosections, namely, an upper one generally indicated by thereference'character 22 in Fig. 2 and a lower section generally indicatedby the reference character 23 in Fig. 2. Referring to Fig. 3, the upperhead section 22 comprises a ring 24 which has an outer circumferentialgroove and ilat upper and lower surfaces. 'I'he ring 24 is rigidlysecured, as by welding, to a pair of side plates 26 and 21 which areparallel to a plane extending transversely of' the tractor through theaxis of the ring 24 and are equally spaced from saidplane at oppositesides of the latter. 'I'he side plates 28 and 21 are connected togetherat their ends facing the tractor by a cross-plate 28. A forwardsupporting trunnion 29 is boltedv to the forward side plate 26 of theupper head section in offset relation to the axisof the ring 24, theaxis of the forward supporting trunnion 29 extending at right angles tothe mentioned transverse plane through the axis of the ring 24. Thetrunnion 29 is centered in an opening -30 of the plate 26. A rearwardsupporting trunnion 3| is rigidly secured yto the rearward side plate 21in axial alinement with the forward supporting trunnion 29, and the twotrunnions are journaled in the mentioned journal bearings at the outerends of the drag frame arms I 6 and I1, 4and are retained against axialdisplacement l relative thereto by suitable shoulders as shown in Fig.4. Rising upwardly from the side plates 28 and 21 at opposite sides ofthe mentioned transverse plane through the axis of the ring 24 andconverging towards each other are two plate members- 32 and ,33, theseplates being connected along their edges facing the tractor by atriangular plate 34, the plate 34 being preferably welded to theconverging plates 32 and 33 and extending beyond the upper edges ofthese plates, as best'shown in Fig. 3. A pair of bearing plates 36 and31 are disposed parallel to the mentioned transverse plane through theaxis of the ring 24 at the upper ends of the converging side plates 32and 33 and are secured in position by welded connections with these sideplates and with the upward extension of the rear plate 34.

The lower section of the mower head comprises a plate member 38 whichextends in a plane parallel to the plane of the ring 24, the outline ofthe plate 38 being best shown in Fig. 5. As shown in this figure, theplate 38 has a central portion underlying the ring 24, and forwardly andrearwardly tapering portions at diametrically opposite sides of the ring24, the forwardly tapering portion being rounded at its forwardextremity .and the rearwardly tapering portion being squared oi by astraight edge. The plate 38 has a circular aperture concentric with thering 24, and a circular shoulder 40 (Fig. 3) formed by an annular recessin its upper side which annular recess accommodates a portion of thering 24 at the lower side thereof, as shown in Fig. 3. In order toretain the plate 38 on the ring 24, a retaining ring 39 is secured tothe upper side of the plate 38 by an annular series of bolts 4I. Theretaining ring 39 projects into the outer circumi'erential groove of thering 24, and for purposes of assembly this ring is made in two halves,as shown in Fig. 5, relatively adjacent face portions 42 of the ringhalves being slightly spaced from andjextendingparallel to each other.Secured to the tapering `forward and rearward portions of the plate 38and forming part of the lower head vsection are two hangers 43 and 44,(Fig. 4), the front hanger 43 consisting of a plate member dependingfrom the lower side of the plate 38 and having a slotted opening 46, andthe rear hanger 44 comprising two lugs depending from the plate 38 andforming a support for a pivot pin 41.

It will be noted that the rings 24 and 39 constitute a ring joint whichconnects the upper and lower head sections for rotation relative to eachother and which affords a passage between the head sections axially ofthe ring joint. The ring joint also functions to center the aperture ofthe lower head section on the axis ofthe ring 24.

Mounted on the front and rear hangers 43 and 44 of the lower head.section is an inner cutter bar shoe in the form'of a fabricatedstructure, the shoe comprising a heavy-plate section 48 and a lighterplate section 49 forwardly of the plate section 48. T he rear end of theheavier plate section 48 is curved upwardly and carries a lug 5I whichis pivotally secured between the lugs of the rear hanger 44 by means ofthe pivot pin 41. The lighter shoe plate 49 is also curved upwardly andcarries a lug 52 which in turn is secured to the front hanger 43 bymeans of a bolt connection 53. The bolt connection 53 consists of a boltand a n ut thereon, the bolt extending through a hole in the lug 52 andthrough the slotted aperture 46 ofthe front hanger 43, and the nut beingtightened on the bolt so as to retain the lug' 52 rmly in contact with.front erally indicated in Fig. 1 by the reference char' acter 54,Acomprises a cutter bar 56, best shown m Fig. 6, and a knife bar r1,which 1s mounted on the cutter bar in conventional manner forreciprocating movement longitudinally thereof.

swathboard, as may be seen from Figs. 1 and 6.

A wear plate 45 underlying the shoe sections 48 and 49 of the inner shoehas an uptur'ned rearward portion which is secu'red by a bolt connectionto a block 58 on the` rear lug 5I of the shoe. An upturned forwardportion of the wear plate 45 is secured to the forward portion of theshoe section 48 by another 'bolted connection 58 which also retains agrass rod 55 in position on the shoe.

The inner end of the cutter bar 56 extends over the plate section 48 ofthe shoe and is rigidly secured thereto in the following manner." As

4shown in Fig. 4, the underside of the cutter bar 56 has a milled outlongitudinal recess, and a key plate 6| which is rigidly secured to thetop oi` the plate section48 is received within the recess at theunderside of the cutter bar 56. A back strap 62 adjacent to the verticalrear face of the cutter bar 58 is also rigidly secured to the Platesection 48, and the cutter bar is thus retained against horizontalangular displacement relative to the plate section 48. A wear plate 63is placed on top of the cutter bar 56, and a spacer strap 64 and aretainer strap 68 rest on top of the wear plate 63. A bolt G1 has acountersunk head in the retainer strap 68 and extends downwardly throughthe retainer strap, the spacer strap 64, the wear plate 63 and the keyplate 6|, into a countersunk opening of the shoe plate 48. A nut 88within the countersunk portion of the opening in the shoe plate 48 isthreaded upon the lower end of the bolt 81 and tightened thereon toretain the parts in assembled position, a lock washer being interposedbetween the nut 68 and the shoe plate 48. Additional bolts assisting thebolt 61 in retaining the parts in assembled position may be provided ifnecessary or desirable.

Another stack of plate members is mounted on `f the shoe section 48 inadvance of the cutter bar 56, the forward stack of plate members comheadplate 18 rests on the wear plates 63 and 1| and ls retained againstupward movement by the retainer plates 66 and 14. The head plate 18 isthus guided on the inner shoe of the mower arm for reciprocatingmovement transversely of the inner shoe.

From the foregoing description of -the connection between the cutter barand the inner shoe it will be seen that the cutter bar is rigidlysecured to the inner shoe while the knife bar is reciprocablelongitudinally of the cutter bar and transversely of the shoe. The mowershoe in turn is connected to the lower section of the mower head by therearward pivot pin 41 and the bolted connection 53 and is normallyretained in fixed position on the lower section of the mower head butmay be tilted, as stated, about .the axis of the pivot pin- 41, that is,about an axis extending longitudinally of the cutter bar. The ring jointwhich connects the lower head section to the upper head section permitsYrotary displacement of the lower head section relative to the upper headsection about the axis of the ring joint, but the head sections areincapable of relative movement other than rotary movement about the axisof the ring joint.

Referring to Figs. 4 and 5, a locking pin 19 is secured in an upstandingposition on the forwardly tapering portion of the lower` head plate 38,as best shown in Fig. 4. As shown in Fig. 5, the locking pin 18 isengaged by a latch 8| which is pivotally mounted at 85 on a bracketsecured to the forward supporting trunnion 29. The bracket for the latch8| comprises two vertically spaced triangular plate members 82 which arewelded to the front face of the supporting trunnion 29, and a supportinglug 83 is secured between the bracket plates 82 and extends forwardlytherefrom in front of the supporting trunnion 28. The latch 8| comprisestwo vertically spaced plates in the same planes as the plates 82', and abolt extending through the latch plates 8| and prising a bottomplate 69corresponding in thickl ness to the full thickness of the cutter bar 56,a wear plate 1| corresponding to the wear plate 83, a spacer strap 12corresponding to thel spacer strap 84, and a retainer strap-14corresponding to the retainer strap 66. A bolt 16, corresponding to thebolt 61, has a countersunk head in the retainer strap 14 and extendsdownwardly through the spacer strap 12, wear plate 1| and bottom plate88 into a countersunk forward opening of the shoe plate 48. A lockwasher and a nut 11 on the bolt 16 are received within the countersunkportion of the forward hole in the shoe plate 48, the nut 11 beingtightened to hold the forward stack of straps together. i. Suitableprovisions are made to secure the forward stack eye-bolt 84.

between the latch and its supporting bracket. The latch 8| isresiliently pressed against the locking pin 19 by a spring mechanismvwhich cornprises a long eye-bolt 84 which extends through the spacebetween the latchplates 8| into the space between the bracket plates 82.A bolt 88 extending through the bracket plates 82 and the eye of theeye-bolt 84 secures theeye-bolt for pivotal movement on the bracket 82.'Slidably fitted upon the shank of the eye-bolt 84 is a thrust `block 81which has a cylindrical surface seated in semicylindrical recesses ofthe latch plates 8|, and a spring 88 urges the thrust block 81 icto therecesses of the latch plates 8|. The spring 88 bears at one end upon the4thrust block 81 and at its other end against a washer 89 which abutsagainst a nut 8| on the threaded portion of the eye-bolt 84. A jam nut92 is drawn up against the nut 8| to lock it on the be adjusted by meansof the nuts 9| and 92.

It will be noted that the latch 8| cooperating with the locking pin 18releasably secures the lower section of the mower head against rotationrelative to the upper head section about the axis of the ring jointcomprising the rings 24 and 39.

It will further be noted that the lower head section is releasablylocked by the latch 8| and locking pin 19 relative to the upper headsection in such a position as to dispose the mower arm 54 transverselyof the tractor. From the locked position of the lower head section whichis shown The tension of the spring 88 may Y the mower strikes anobstruction such as a large stone or a tree stump hidden in the grass.The break-back movement' protects the machine V- against damage whichwould otherwise be caused by continued advance movement of the tractor.'Ihe tension of the spring 86 is so adjusted that the cutterd bar willremain in its normal cutting position transversely'of the tractorunderordinary cutting strains, but when the cutter bar encounters anobstruction while the mower is in progress', the pressure of the lockingpin 19 upon the latch 8| will become sufiiciently high to force thelatch 8| against the pressure of the spring 88 out of engagement withthe pin 19 and thus permit the cutter bar to break back. The path ofmovement of the locking pin 19 during the breakback movementl isindicated by two dash-dotted line positions of this pin in Fig. 5. Itwill also be noted that during the break-back movement, the lower headsection is guided upon the upper head section by the coaction of thelower head plate 38 and the ring 39 with the ring 24 of the upper headsection. After the obstruction has been cleared,`it is-only necessaryfor the operator to rest the rear edge of the cutter bar against asaasssand |08 mounted within the hollow trunnion 0| support the drive shaft|06 for rotation coaxially with the trunnion 3|, the roller bearingsbeing suitably mounted within` the trunnion 3| and on the drive shaft|06 so as'to retain the drive shaft |06 against axial displacementrelative to the trunnion 3|. An' oil seal |09 adjacent to the plate 21of the upper head section and an oil the obstruction and drive thetractor a short dis- K tance in reverse', and such rear movement of thetractor will then cause rotation of the lower head section relative tothe upper head section so as to restore the cutter bar to its normalposition and to reengage the latch 8| with the locking pin 19. The latch8| has a suitable slanting surface 93 along which the locking pin 19 mayslide into locking engagement with the latch 8| while the cutter bar isbeing restored to its normal working position.

Referring now to the mechanism for transmitting driving power to theknife bar 51, Fig. 2 of the drawings shows a power takeoi shaft 95extending rearwardly from the rear axle housing of the tractor, and asheave 94 mounted on said power takeoff shaft, the power takeoffshaftreceiving power from the engine of the tractor in a conventionalmanner. Mounted below the central portion of the rear axle structure 1is a supplemental frame 96 on which an auxiliary shaft 91 is journaledin a position below the power takeoi shaft of the tractor. The auxiliaryshaft 91 carries a sheave 98, and a belt |00 trainedover the sheavesV 94and 98 transmits rotation of the power takeoff shaft to the auxiliaryshaft 91. The auxiliary shaft 91 extends longitudinally of the tractorand another auxiliary shaft 99 extending longitudinally ofthe tractorisv mounted at the lower end ofthe bracket portion |4 for seal fittedinto a cap 2 at the rear end of the trunnion are provided to protect theroller bearings against dirt and to provide for the retention oflubricant within the axial bore of the trunnion 3|. A crank pin ||3issecured to a flywheel portion ||4 of the drive shaft 06 in the spacebetween the side plates 26 and 21 o'f the upper head section overlyingthe apertures of the ring 24 and of the lower head plate 38.

Fig. 4 shows the crank pin ||3 in its lowermost position while Figs. 3and 5 show the crank pin rotated into a horizontal plane through thedrive shaft 06. The hole 30 inthe side plate 26 permits passage of theshaft |06 and flywheel ||4 therethrough for purposes of assembly,beforeinstallation ofthe trunnion 29.

In connection with the description of the upper head section it hasheretofore been mentioned that a pair of bearing plates 36 and 31 aresecured to the upper end of said head section. A pivot pin ||6 ismounted in these bearing plates 36 and 31 on an axis parallelto the axisof the drive shaft |06, and an arm ||1 is swingably mounted on the pivotpin ||6 between the bearing plates 36 and 31. An eye on the arm |1 isclosely fitted between the bearing platesl 36 and 31, and the arm isthus retained for swinging movement transversely of' the axis of thedrive shaft |06. The pivot pin ||6 is moreover located in such positionon the upper head section that its axis lies directly above the centerof the ring joint 24 and 39 or, in other words, the arm ||1 is pivotedat a center on the axis of said ring joint. The arm ||1`extendsdownwardly from the pivot #pin ||6 through the ring 24 into the lowerhead -section, and a ball element ||8 is formed at rotation -about anaxis coinciding with the axis' l `power from the power takeoff` shaft 95to the the lower end of the arm. An enlarged portion of the arm ||1between its upper and lower ends, carries a wrist pin ||9 -which extendsthrough the arm parallel to the pin ||6. The

wrist pin ||9 serves to connect one end lof a pitman |2| to the arm, theother end of the pitman being journaled on the crank pin ||3. As bestshown in Fig. 4, the end of the pitman |2| connected to the arm ||1 isbifurcated and the enlarged portion of the arm ||1 is closely i fittedbetween the forked arms of the pitman |2|,

the wrist pin 9 extending through both arms of the bifurcated portion ofthe pitman |2|, and being suitably retained against axial displacement.

.Rotation of the drive shaft 06 causes oscillatory 'movement of the arm||1 about its pivot center at ||6, and the crank pin ||3 is offset fromthe center of the drive shaft 06 at such a distance that its throw willoscillate the arm ||1 within the limits of the ring 24. The limitsconnections with the i ofthe throw at the lower end of the arm are plate18 Aarm ||1 is embraced by of 9. link |23, the socket |22 heiligsplitandthe loose half being secured to the `link |23 by a rpair of bolts |24.The other end'of the link |23 has a ball and socket connection with. thehead plate 18 -of the knife bar 51. |26 is supported on a-base securedto the head between the retainer plates 66 as showntionof the splitsocket/I order to insure proper A ball element and '14 in Fig. 4,'andthe-link I23-has a ksplit 'socket |21 engaging-the ball |26. The cappor- 21 embracing the ball |26 is secured to the link |23 by a pair ofbolts 'The link |23 due to its ball and. socket connections withthearm||1 and theknife bar `-51"transmits oscillatory movement vof :the armtween the shaft |06 andarm ||1 itself, are shielded-bythe side walls 2632 fand-33 of thev ball and socket' connection M8, |22,

center of the ball and socket connection |26, |21- joint' comprising thethe cutter bar breaks ||1 to l'thelrnifeban andthe knife-bar,

full linel position of the'-cutter bar shown in Fig. 5, is thusreciprocated with a full 'cutting stroke longitudinally of theoutter'barby rotavtion of the shaft line from the pivot center l'|6`-I06 which shaft,1 in turn, is

` 'before in connection v arm ||1 and the knife bar 61. It should beunderstood, however, that `the ball and socket connections are onlyapreferred way of accomplishing the desired result, and that theinvention isnotlimited to the illustrated specic' construction; Vsinceother arrangements could obviouslybe made to accomplish the necessaryilexibilitypf the drive. The ball and socket connections of the link|23.with the arm ||1 and the knife bar 51 are considered preferable finoperation of the'fidrive when the cutter bar is tilted about the'f'axisof the pivot `pin 41, as has been describedihereinwith the boltconnection 53.

Fig. l, as'stated, shows the mowingvarm 'raised to a'postlon forcutting' on an incline laterally of the tractor. From the position shown`in Fig.

1, the cutter bar maybe lowered to 'position for cutting pn`level groundby tilting adjustment of the upper and lowerjhead sections on`the dragarms"|6 and '|1. as illustrated' in Fig.` 3.' As

` stated,l the' forward and rearward supporting 'trunnions 29'and 3l arejournaled onthe drag arms, and when the head comprising thetwo'secdriven bythe power takeoff. .of ythe `tractor as has beenexplained hereinbefore. 1

It will be noted that thepitman connection beand 21 and by th'e wallportions theupper head section, and thatthe wall porvtions 28 and 34 ofthe upper head section further yshield the moving parts. .withintheupper head section. f Y

It will also be noted'that the linki|23 is con--y nected to the knifebar in such. a manner that a ofthe arm ||1 the knife bar will be on theupper head'section,` through .the center of 4 to the extends through thepassage afforded by the ring rings |26 on the knife 'bar moves out ofthe plane of. swinging movement of the arm ||1 into an acutel s anglerelation to. said plane as is illustrated .by

, end of said arm. A full `lines in Fig. 5,

the dash-dotted line position of the cutter bar inFig.

5. During such movementthe link |23I will be turned on the arm ||1 aboutthe center.

of the ball and socket connection transmitted, as stated, to the knifebar in the position of the cutter bar, which is shown in full andyassuming that the arm 1 at thelowerl cutting stroke is'being 4continues` to oscillate during the break-back. i

movement of the cutter bar, the stroke transrnitted to the knife bardecreasesvas the breakback travel of the cutter bar 'be seen, however,that the `driving mechanism may continuel to operate Without binding inany way even if the cutter bar should `be swung back to a positionparallel tothe direction of propulsion of the tractor, in which casereciprocation of the knife bar would cease entirely.

' The necessary flexibility of the drive to per-4 mit its continuedoperation, lwithout binding,V during. break-back movement of the cutterbar is accomplished by. the link and its ball and socket increases. Itwill ons f tilted up or down on in. tha f.

.center of the ar the knife `bar which is fthe'narm l'l1f`remainsunchanged irrespective of whether the cutterbar is 'adjusted to ahorizontal cutting' position or tween the positions the mower'head insuch relation to the tractor that when cutting o'n a bank the tractorthe drag arms I6` 29 and 3|l rotate vin the bear- `'and |1 the journalsof these drag arms. Durings at the outer ends fing suchftilting movementof thel head its upper and lower sections lmoveV in unison about theaxis A `of the drive shaft |06;` and the inner Vshoe `and ,the mowingarm 64 move in unison with' the head. When the` head is tilted inthementioned manl ner, the' pin |`|`6 which constitutes the swinging I |1,and the axis of the ring Joint, 36 remain" in their predetermined rela-,tion to the axis o'f'the drive shaft |06. Itwill be seen that due tothis varrangement the throw of isran'sinitt'ed thereto by nto anupwardly inclined cutting position as show njinjlig. 1. "In other words,n reciprocated'witha full cutting stroke in any adjustment of thec'utterbar about the axis of the trunnions 29 and 3|.

' It should' also be: noted vthat Vthe mower head shown in Fig; 3; so asto raise the outer end of theicutterv bar through an angle of ninetydegrees ormore, such tilting movement of the mower head being notobstructed byv any Vparts of the drag frame comprising the arms I6 andI1. Nor is such tilting movement of the mower head obvstru'cted by thetractor or anyparts'jthereon,

vsince the drag arms are sumciently long to position the headclear ofthe tractor. As shown in Fig. 2, the axis-of the supporting trunnions onwhich the head swings relative to the drag frame is located in proximityto theA plane of rotation of the front and rear wheels 2 and 3 at themower side of the tractor. This location of the trunnion axisnot onlyaffords ample clearance bemower head and the tractor, but also may runonlevel ground'close to the bank while the cutterV bar extendsI upwardlyparallel to they l inclined bank surface.

The'mower head may also be tilted' from the angle .fof forty-,fivedegrees, or more, such tilting movement. being likewise not obstructedby the drag` frame or anyy parts' of the tractor. The

position f`vertical angular the position inwhich it is position inwhich, it is shown in Fig. 3. so as to lower the outer end of the cutterbar through an total range' of vertical swinging movementof the outercutter bar end about the axis of the trunnion's 29 and 3| relative tothe drag frame is ample for all practical requirements, and the knifebar is reciprocated with a full cutting stroke v throughout the range ofsaid vertical swinging movement of the cutter bar.

The axis of break-back movement of the cutter bar, which is the axis ofthe ring joint 24, 39, swings with the head about the axis of thetrunnions 29, 3|, and whenthe cutter bar encounters an obstruction-whileworking on an upward or downward incline, it is released with the sameefficiency by the latch 8|, as whenit encounters an obstruction whileworking on level ground. In other words,.the operation of the releasablelatch mechanism 19, 8| is not affected ,by pivotal up or downadjustments of the cutter bar relative to the drag frame I6, |'I vfromthe horizontal l position of the cutter bar' shown in Fig. 2.

In addition to the vertical tilting adjustment of the. cutter bar aboutthe axis of said trunnions 29 and 3|, which has just been mentioned, the

cutter barmay also be raised andloweredby swinging movement of the dragframe about the axis of its pivotal connection with thelower portion I4of the -bracket I2. The drag frame I5, I'I may be pivotally adjusted inthe mentioned manner irrespective ofwhether the cutter barl extendshorizontally or at an incline as 'shownl in Fig. 1, without affecting orchanging the throw of the knife bar, and without'affecting the operationof the release mechanism 19, 8|, as should be obvious from the foregoingdiscussions.

The mentioned adjustment of the drag arms I6 and |'|,l about their pivotcenter on the portion I4 of the bracket l2, and the pivotal adjustmentof the mower head about theaxis of the supporting trunnions 29 and 3| ispreferably effected by power and, as shown in Figs. 1 and 2, this isaccomplished by means of hydraulically operated rams.

A lifting ram for the drag arms I6 and I1 comprises a ram cylinder |29the lower end of which is pivotally connected at I 3| (Fig. 2), to theforward drag arm I6, the point |3l being spaced a suitable distance fromthe pivot center of the drag arm on the portion I4 of the bracket |2. Apiston rod |32 vextends upwardly from the ram cylinder |29 and ispivotally connected to the upper arm I3 of the bracket l2 at |33. Theram cylinder |29 is connected with a hydraulic control mechanism |34 onthe tractor by a hose |36, and the ram comprising the cylinder |29extending arm pivotally connected with the ram' cylinder |31. 'I'he ramcylinder |31 rests loosely on a stop |39 carried by a. bracket |43 whichis secured to the web |8. The piston rod |38 of the tilting ram carriesa sheave |4I, and another sheave |42 is rotatably mounted on the bracket|43. A cable |44 is anchored at one end near the lower end of thebracket portion I4, the hanger |35 having another arm for fastening thecable |44 thereto. The cable |44 extends from the hanger over the sheaveA|4| and is then trained around the sheave |42 from which it extends toan anchor pin |46 on the side plate 33 of the upper head section. Thetilting ramlift ram cylinder |31 the upper section of the A mower headmay be permitted to swing in a.

clockwise'direction, as viewed in'Fig. 2about theI axis of thesupporting trunnions -2`9 and 3|.

A pump |41 is mounted in front of the engine unit of" the tractor asshown in Fig. 1, the pump being operatively connected with thecrankshaft of theengine. Hose connections |48 place the pump |41 -incommunication with the control.

mechanism |34 on the tractor, the'pump` being effective to supplysuitable hydraulic pressure for actuating the lifting ram for the dragVarms I 5 and Vl1 andthe tilting ram for the mower head.

suitame contra levers |49 and 45| furthe hydraulic control' mechanism|34 are arranged within reach from the driyers seat |52 on the tractor.By manipulation of one of the control'levers |43 and l5| thevlifting rammay be operated,IA and by manipulation lof the other control lever theVtilting .raml may be operated. The lifting ram and the tilting ram maybe operated independently of veach other by manipulation of the controllevers |49 and |5I. By manipulation of the control lever for the liftingram alone, the drag frame and the mower arm will be moved as 'a unitabout the pivot center of the dragY frame on the bracket portion I4,that is, about the axis of the auxiliary shaft 99. Bymanipulation of thecontrol lever for the tilting ram alone, the mower' arm is swung aboutthe axis of the supporting trumiions 29 and 3| while the drag frameremains stationary relative to the tractor. The mower arm may beadjusted froma position in which it rests on the ground to an elevatedposition above the ground by first actuating the lifting ram, whichraises the cutter bar above the ground and puts it at a slight upwardinclination relative to the ground, and by thenmanlpulating the tiltingram so as to position the mower arm parallel to the ground. A

While in the foregoing a preferred embodiment of the invention has beenshown and described, it should be understood that it is not intended tolimit the invention tothe exact details of constructionherein disclosedfor various modificalons within the scope of the appended claims mayoccur to persons skilled in the art.

-It is claimed and desired to secure by Letters Patent:

1. In combination with a tractor having a body and supporting wheels atopposite sides thereof, a drag frame mounted on said tractor body forvertical adjustment relative thereto and extending laterally therefrom,a cutter bar having an inner end laterally of said tractor, meansconnecting said cutter bar at said inner end thereof .to a portion ofsaid drag frame in proximity to said arm for driving said said dragframe, an arm mounted on mounted on said bracket for swinging movement`relative thereto about a center spaced from the axis of said driveelement, and means including knife bar from said drive elementwith afull stroke of reciprocating movement insaid cutting position of saidcutter i l bar irrespective of the height to which its outer end hasbeen moved by said vertical angular movement thereof. a

2. In combination with a tractor having a body and supporting wheels atopposite sides thereof,

a drag frame mounted on said tractor body for verticaladjustmentrelative thereto and extending laterally therefrom, a mower headcomprising aviirst and a second section connected together for rotationrelative to each other about a common axis, means connecting said iirsthead section with a portion of said drag frame in proximity to the planeof rotation of one of said supporting wheels for swinging movement ofsaid iirst head section relative to said drag frame about an axisextending lengthwise of said tractor and transversely of said commonaxis of said head sections, a cutter bar secured to said second headsection, means including a; locking mechanism releasable by saidrelative rotation of said head sections, for retaining said cutter barin a cutting position transversely of said tractor, a knife barreciprocably mounted on said cutter bar, an arm swingably mounted onsaid first head section, and means including said arm for transmitting afull stroke of reciprocating movement to said knife bar in said cuttingposition of said cutter bar irrespective of angular displacement of saidcutter bar by said swinging movement of said first head section relativeto said drag frame.

3. In combination with a tractor having a body and supporting wheels atopposite sides thereof, a drag frame mounted on said tractor body forvertical adjustment relative thereto and extending laterally therefrom,a mower head comprising a first and a second section connected togetherfor rotation relative to each other about a common axis, meansconnecting said first head section with a portion of said drag frame inproximity to the piane of rotation of one of said supporting wheels forswinging movement of said first headl section relative to said dragframe about about an axis extending lengthwise of said tractor andtransversely of said common axis of said head sections, a cutter barsecured to said second head section, means including a locking mechanismreleasable by said relative rotation of said head sections, forretaining said cutter bar in a cutting position transversely of saidtractor,`

a knife bar reciprocably mounted on said cutter journaled in fixedposition relative to said drag frame for rotary movement about an axisin line with the axis of swinging movement of said first head sectionrelative to said first head section for swinging movement about a centerin proximity to said common axis of said head sections and spaced fromsaid ax of swinging bar, a drive element l'Iii movement of said rst headsection, means connecting said drive element with said arm foroscillating the latter by vrotation of said drive element, and meansconnecting said arm with said for rotation relative to each other abouta com- 1 mon axis, means connectingsaid iirst head section with aportion of said drag frame in proximity to the plane of rotation of. oneof said supporting wheels for swinging movement of said first headsection relative to said drag frame aboutan axis extending iengthwiseofsaid tractor andtransversely of said lcommon axis of said head sections,a cutter bar connected with said' second head section for tiltingadjustment relative thereto about an axis extending longitudinally ofsaid cutter bar, means including a locking mechanism releasable by saidrelative rotation of said head sections for retaining said cutter bar ina cutting position transversely vof said tractor, a knife bai;reciprocably mounted on said cutter bar, and driving means for saidknife bar accommodating said swinging movement of said first headsection relative to said drag frame, said relative rotation of said headsections and said tilting adjustment of said cutter bar.

5. In -a mower having a cutter bar and a knife bar reciprocablelongitudinally of said cutter bar, the combination of a drag frame, amower head comprising a first and a second section connected togetherfor rotation relative to each other about a common axis, meansconnecting said iirst head section with .said drag frame for swingingmovement relative thereto about an axis extending substantially in thedirection of propulsion of the mower and transversely of said commonaxis of `said head sections, means connecting said cutter bar with saidsecond head section for tilting adjustment relative thereto about anaxis extending longitudinally of said cutter bar, means including alocking mechanism releasable by said relative rotation of said headsections, for retaining said cutter bar in a cutting positiontransversely of the direction of propulsion of the mower, a drii/eelement journaled in fixed position relative to said drag frame forrotary movement about said axis of swinging movement of said iirst headsection relative to said drag frame, an arm mounted on said first headsection vfor swinging movement about a center in proximity to saidcommon axis of said head sections and spaced from said axis of swingingmovement of said first head section, means connecting said arm with saiddrive element for oscillating said arm by rotation of said driveelement, and a link having a ball and socket connection at one end withsaid arm and another ball and socket connection at its other end withsaid knife bar.

6. In a mower, a nrst and a second head section, a ring joint comprisinga pairof coaxial ring elements connected together for rotation relativeto each other about their common axis and secured, respectively, to saidhead sections to form a passage therebetween axially of said axis ofsaid ring joint, a movable cutting element supportingly connected withone of said head sections, and -a power transmitting connection betweensaid arm and said cutting element.

'7. In a mower, a first and a second head section, a ring jointconnecting said vhead sections for rotation relative to each -other andalfording a passage therebetween axially of said ring joint, an armextending into said passage, power 'actus ated means on said rst headsection operable to oscillate said arm transversely of the axis of saidring joint, a reciprocable cutting element supportingly connected withsaid second head section, and a power transmitting connection betweensaid arm and said cutting element lfor reciprocating the latter by saidoscillatory movement of said arm.

-8. In a mower, a first and a second head `sec tion,- a ringr jointconnecting said head sections for rotation relative to each other andaffording a passage therebetween axially of said ring joint, an armextending through said passage, means on said first head sectionsecuring said arm at one end thereof to said first head section foroscillatory movement of the other end of said arm transversely of theaxis of said ring joint about a center in proximity to said axis, poweractuated means operable to oscillate said arm about said center, areciprocable cutting element supportingly connected with said secondhead section, and a driving connection between said arm and said cuttingelement including a power transmitting element loosely connected to saidother end of said arm. Y

9. In a mower, a first head section having a hollow supporting trunnion,a second head section, a .ring joint connecting said head sections forrelative rotation. about an axis extending transversely of the axis ofsaid trunnion, a rotatable drive shaft extending axially through saidtrunnion, an arm swingably secured to said first head section at oneside of said ring joint and tion, a ring joint connecting said headsections for rotation relative to each other and affording a passagetherebetween axially of said ring joint.'I a drive shaft, meansretaining said drive shaft in angularly fixed position relative to rsaidrst head section for rotation about an axis extending transversely ofthe axis of said ring joint at one side of the latter, a cutter barsecured to said second head section at the other side of said ring jointfor tiltingv adjustment about an axis extending longitudinally of saidcutter bar, a knife bar reciprocably mounted on said cutter bar, an armand a link having relatively adjacent ends connected by a first ball andsocket joint, means connecting said arm with said first head section atsaid first side of said ring joint, for swinging movement about a centerin proximity to the axis of said ring joint, a second ball and socketjoint connecting said link with said knife bar in such a position that aline from said swinging center of said arm through the center of saidiirst ball 'and socket joint to the center of said second ball andsocket joint extends through said passage, and a 4 driving connectionbetween said drive shaft and said arm for oscillating said arm aboutsaid swinging center thereof by rotation of said drive shaft.

12. In a mower, a first and a second head section, a ring jointconnecting said head sections for rotation relative to each other andaffording a passage therebetween axially of said ringl joint, an armextending through said passage," means on said first head sectioncooperating with said arrr. to guide the latter for swingingy movementin a plane extending, in angularly fixed relation to said first headsection, through the axis of said ring joint, a reciprocable cuttingelement supextending therethrough into said second head section, a powertransmitting connection between said shaft and said arm for oscillatingthe latter about its centergof sva'nging movement on said first headsection, a reciprocabie cutting element supportingly connected with saidsecond head section, a link swingably secured to said arm at the otherside of said ring joint, and means operatively connecting said Alinkwith said cutting element.

10. Ina mower, av first and a second head section, a ringjoint'connecting said head sections for rotation relative to each otherand aifording a passage therebetween axially of said ring joint, a driveshaft, means retaining said drive shaft in angularly xed positionrelative to said first head section for rotation about an axis extendingtransversely of the axis of said ring joint at one side of the latter, areciprocable cutting element supportingly connected with said secondhead section at the other side of said ring joint, an arm pivoted onsaid rst head section for swinging movement relative thereto about acenter at said first side of said ring joint, means drivingly connectingsaid arm with said shaft to oscillate said arm about said center byrotation of said shaft, and a driving connection between. said arm andsaid cutting element including a power transmitting element extendingthrough said passage and operable by said arm to move back and forthwithin said passage transversely of the axis of portingly connected withsaid second head section, means positioning said cutting element forreciprocating movement longitudinally of said plane including amechanism releasably locking said head sections against rotationrelative to each other about the axis of said ring joint, and a powertransmitting connection between said arm and said cutting element forreciprocating the latter by swinging movement of said arm, said powertransmitting connection including a link secured to said arm for pivotalmovement relative thereto so as to accommodate said relative rotation ofsaid head sections upon release of said locking mechanism.

13. In a mower, a cutter bar having a shoe at one end, a lower headsection bridging said shoe and having an aperture therein above saidshoe, means connecting said lower head section with said shoe, an upperhead section having a ring element cooperating with said lower headsection to centersaid aperture of the latter on the axis of said ringelement and vto secure said lower head section to said upper headsection for rotation relative thereto about said axis, said upper headsection including a wall structure forming a hood over said aperture ofsaid lower head section and having a pair of relatively spacedsupporting trunnions alined on an axis extending transversely of theaxis of said ring element, an arm within said hood swingably securedthereto on a center in proximity to the axis of said ring element andextending through the latter and said aperture of said lower headsection, a rotatable shaft extending axially through one of saidtrunnions, a power transmitting connection Within said hood between saidshaft and said arm for oscillating the latter about Said center, a knifebar for reciprocatbar mounted on said cutter ing movement longitudinallythereof, and a, link swingably connected at one end to said arm at ayportion thereof below said ring element and at its other end to saidknife bar.

14. In a mower, `a cutter at one end, a lower head section bridging saidshoe and having an aperture therein above said shoe, means connectingsaid shoe with said lower head section for tilting adjustment relativethereto about an axis extending longitudinally of said cutter bar, anupper head section having a ring element cooperating with said lowerhead section to` center said aperture of the latter on the axis of saidring element and to-secure said lower head section to said upper headsection for rotation relative thereto about the axis of said ringelement, said upper head section including a wall bar having a shoestructure forming a hood over said aperture of said lower head sectionand having 'a pair of re1- atively spaced supporting trunnions alined onan' axis extending transversely of the axis of said ring element, an armwithin said hood swingably' secured thereto on a center in proximity tothe axis of said ring element and extending through the latter and saidaperture of said lower head section, a rotatable shaft extending axiallythrough one of said trunnions, a power transmitting connection withinsaid hood between said shaft and said arm for oscillating th latterabout said center, a knife bar mounted on said cutter bar forreciprocating movement longitum dinally thereof, and a link having aball and socket connection at one end with a portion of said arm belowsaid ring element and another ball and socket connection with said knifebar. BOYD S. OBERLINK.

